August 29 (HealthDay News) -- The majority of youths who are tried in criminal courts as adults have a psychiatric disorder, researchers report.

Juveniles who are transferred to adult court, known as "transferred youths," are a growing population. Between 1983 and 1998, the number of transferred youths in the United States almost quadrupled.

In a study in the September issue of Psychiatric Services, Jason J. Washburn of Chicago's Northwestern University Feinberg School of Medicine and colleagues examined the cases of 1,715 youths, aged 13 to 18, who were processed in the Cook County Juvenile Temporary Detention Center in Chicago. Of the youths, 275 were transferred to adult court.

The researchers found that more than two-thirds (68 percent) of the transferred youths had a psychiatric disorder, and almost half (43 percent) had two or more types of disorders. The transferred youths who were eventually sentenced to prison had even higher rates of psychiatric disorders.

Another finding was that black and Hispanic males were more likely than non-Hispanic whites to be transferred, even when the researchers controlled for violent crime. This is important, since there is evidence that males from minority groups are among the least likely to receive mental health treatment, either in the community or in prison.

"This finding suggests an urgent situation in which the largest numbers of transferred youths in need of psychiatric services are also the least likely to receive them," the study authors wrote.

SOURCE: American Psychiatric Association, news release, Aug. 29, 2008